Mauser Modelo Argentino 1909

[Low & Slow]

Mine likes 4064 as well. By the way, I don't think your crest was ground. I believe that it's just worn down. It's pretty close to the natural balance point carried in trail, and being in the white, they can succumb to perspiration. Mine shows similar erosion, although not quite to that degree. There is no doubt that my '91's receiver was was ground, in comparison.